The longer and smarter somebody has trained the more their bodies will be able to handle due to the accustomed stress their bodies have learnt to adapt to.
of course, without enough knowledge and listening to ones body regarding food choices and sleep amounts, a body can become overtrained, however advanced trainers know when and what their body requires, and increase workloads at slow paces.
I agree! I think the most important thing in bodybuilding is to follow your instincts, and learn what your feelings mean.
I always felt like the best way to train was to blast the muscle as much as possible, aiming for huge soreness, then let the muscle recover until there was no more soreness, and do it again. It seems like no matter how hard I hit a muscle, I could never get it sore for more than about 3 days (legs a little longer), so I would always aim to hit each muscle twice a week.
This worked great for a couple months when I first started eating enough to actually grow, and then about three months later I changed everything for a really stupid reason and ever since I haven't been able to get consistent growth, or even much growth at all.
This period of growth was about 3-4 years ago and these days things just don't seem to work the same. I'll have a great workout, huge pump, decent soreness (never like in the old days though), lift a lot of weight, come back a couple days later when the muscle isn't sore anymore and, like magic, boom, the muscle doesn't do anything. Feels completely dead. Felt fine going into the workout, but it doesn't want to cooperate and I just end up with joint pain, no pump, no soreness, and no weight lifted.
I'm starting to think my body has just changed somehow (maybe hormone levels?) and my life is a lot more stressful now so maybe that has something to do with it... so I decided to cut back the frequency to once a week to see if I just need more time to recover (even though the muscle feels fine going into the workout

).
Though I will say, even though the muscle often feels fine before a crappy workout, usually when I wake up I have an ominous feeling that I shouldn't lift, that my body isn't ready. I wake up and the first thought is "I can't deadlift today..." but then thirty minutes later I feel fine so I just sort of ignore it. This is another reason I'm cutting back -- I'm going to try to actually obey this instinct for once.